Fiberglass mats are made in many weights and sizes and can be used for a variety of applications. A general discussion of glass fiber technology is provided in “Fiber Glass” by J. Gilbert Mohr and William P. Row, Van Nostrand, Reinhold Co., New York 1978, which is hereby incorporated by reference. Fiberglass mats of the nonwoven type are generally known.
In the manufacture of wet laid nonwoven mats containing a large proportion of glass fibers, typically used binders such as urea-formaldehyde resins or polyvinyl acetate, styrene butadiene rubber and acrylic copolymer latexes, will burn. Even polyvinyl chloride resin systems, if not high enough in chloride, will burn and may emit hydrogen chloride and heavy smoke.
Fire retardancy for glass mats has been attempted using various methods. For example, in U.S. Pat. No. 6,368,991, issued to Horner, Jr. et al., there is disclosed a low fiber, plyable facer suitable for use in the construction industry, particularly for insulation board manufacture. The facer comprising a dry preformed fiber mat containing a binder for the fibers preferably a preformed glass mat, coated with a prefoamed composition which contains a thixotropic polymer latex, a foam sustaining amount of a surfactant and a flame retarding and/or strengthening amount of a mineral filler.
U.S. Pat. No. 5,840,413, issued to Kajander, describes a fiberglass mat composition comprising a fiberglass matrix bonded with fire retardant melamine resin binder composition capable of forming a nonwoven mat having at least 27% by weight nitrogen in the dry, but uncured resin, and wherein the mat has no more than a catalytic amount of any phosphorus compound present. In one embodiment, the binder can contain pigments, such as carbon black, in amounts up to 25% based on the weight of the resin binder.
There is a constant search, however, for improvements in the fire retardancy of glass mats, particularly for glass mats to be used as a facer for duct board and equipment liner, so as to impart improved self-extinguishing properties to the laminate. An effective and improved self-extinguishing facer mat would be of great benefit to the duct and liner industry.
It is therefore an object of the present invention to provide a fire retardant fiberglass mat containing a fire retardant agent that is effective and easily and uniformly incorporated into the fire retardant fiberglass mat.
It is also an object of the present invention to provide such a mat which can be suitably used as a facer mat for a duct or equipment liner composite.
These and other objects of the present invention will become apparent to the skilled artisan upon a review of the following description, and the claims appended thereto.